Lubrication mechanism

ABSTRACT

The lubrication mechanism comprises a vertically disposed crank shaft, a laterally movable piston, a connecting rod connecting the crank shaft and the piston, a cylinder barrel housing the crank shaft and the piston, a crank case containing the crank shaft together with the cylinder barrel, a cylinder head forming a combustion chamber, the combustion chamber connecting to a piston movable part end face of the cylinder barrel, an oil filter, and an oil filter installation member in which the oil filter is vertically installed, and the oil filter installation member includes a lubricant detour structure.

INCORPORATION BY REFERENCE

The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2021-017656 filed on Feb. 5, 2021. The content of the application is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a lubrication mechanism.

Description of the Related Art

Heretofore, an outboard motor comprises an engine and an oil filter that filters engine oil (e.g., Japanese Patent Laid-Open No. 11-107732). As a mounting direction of the oil filter onto this outboard motor, a horizontal direction is adopted. In the present structure, residual oil in an oil passage and the oil filter flows out during replacement and maintenance of the oil filter.

To solve the problem, in the conventional outboard motor, eaves are installed under a mounting part of the oil filter, and a range of oil dripping is suppressed, to prevent oil from scattering around.

Also, in recent years, with increase in size of the outboard motor and increase of multi-machine boats, it has been desired to increase efficiency of the replacement and maintenance of the oil filter.

In a conventional technology, oil can be prevented from scattering around, but cleaning with waste cloth or the like is finally required.

To solve the problem, an object of the present invention is to provide a lubrication mechanism in which an oil filter can be replaced without outflow of oil to outside.

SUMMARY OF THE INVENTION

An aspect of the present invention provides a lubrication mechanism comprising a vertically disposed crank shaft, a laterally movable piston, a connecting rod connecting the crank shaft and the piston, a cylinder barrel housing the crank shaft and the piston, a crank case containing the crank shaft together with the cylinder barrel, a cylinder head forming a combustion chamber, the combustion chamber connecting to a piston movable part end face of the cylinder barrel, an oil filter, and an oil filter installation member in which the oil filter is vertically installed, wherein the oil filter installation member includes a lubricant detour structure.

According to another aspect of the present invention, in the above lubrication mechanism, the lubricant detour structure comprises a lubricant detour route formed in the oil filter installation member, and an oil relief valve installed in the lubricant detour route.

According to still another aspect of the present invention, in the lubrication mechanism, the lubricant detour route follows a route other than a filtered lubricant route of the oil filter to return lubricant to an engine.

According to a further aspect of present invention, in the lubrication mechanism, the oil relief valve allows residual lubricant to reflow to the engine, when the oil filter is removed.

According to a further aspect of present invention, in the lubrication mechanism, the oil relief valve comprises a cylindrical valve guide, a spring, and a piston part, the valve guide has an outer circumference formed with a spiral guide hole, the piston part includes a guide pin that fits into the guide hole, with movement of the piston part in an up-down direction, the guide pin moves through the guide hole, the valve guide rotates within a range of 90°, the valve guide has a lower end in which a communication hole opens, and the communication hole is disposed in a relief oil path.

According to a further aspect of the present invention, in the lubrication mechanism, the oil filter installation member has a flange shape with respect to the oil filter.

According to a further aspect of present invention, in the lubrication mechanism, the flange shape is a shape surrounding the oil filter.

A further aspect of present invention provides an outboard motor comprising the lubrication mechanism according to any one of the above aspects.

A still further aspect of present invention provides a ship comprising the above outboard motor.

According to aspects of the present invention, an oil filter can be replaced without outflow of oil to outside.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a starboard side view showing an entire outboard motor;

FIG. 2 is a partially cross-sectional view of an upper part of the outboard motor seen from a starboard side;

FIG. 3 is a perspective view of an oil filter installation member;

FIG. 4 is a cross-sectional view showing the oil filter installation member in a state where an oil filter is mounted;

FIG. 5 is a cross-sectional view showing the oil filter installation member in a state where the oil filter is removed; and

FIG. 6 is an exploded perspective view of an oil relief valve.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a side view of an outboard motor 10 on a starboard side. FIG. 1 shows a main internal mechanism with a dashed line. A direction of an arrow Fr indicates front, and a direction of an arrow Rr indicates rear.

The outboard motor 10 comprises an engine 11 in an upper part. The engine 11 is covered with an upper engine cover 12 and a lower engine cover 13. The upper engine cover 12 is mounted on an upper end of the lower engine cover 13 with a rear hinge 27 and a front stopper 28. A stern bracket 16 is provided in front of the lower engine cover 13. The outboard motor 10 can be mounted on a hull with the stern bracket 16. An extension cover 14 is provided under the lower engine cover 13, and a gear case 15 is provided under the extension cover 14.

Inside the upper engine cover 12, an intake silencer 17 is disposed in front of the engine 11. The intake silencer 17 introduces air (fresh air) into an engine intake port. An electrical component 18 is disposed behind the intake silencer 17. The electrical component 18 performs ignition control of the engine 11, control of a fuel injection device and the like.

FIG. 2 is a partially cross-sectional view of the upper part of the outboard motor 10 seen from a starboard side.

As shown in FIG. 2, the engine 11 comprises a rear cylinder head cover 31, a laterally connecting cylinder head 32, a further laterally connecting cylinder block 33, and a front crank case 34. The cylinder head 32 comprises a combustion chamber 35. The cylinder block 33 comprises a plurality of laterally oriented cylinder barrels 36, and in each of the cylinder barrels 36, a laterally oriented piston 37 is laterally (front-rear direction) slidably housed. The piston 37 has a piston movable part end face being connected to the combustion chamber 35.

A crank shaft 21 is rotatably connected to each piston 37 via a connecting rod 38. The crank shaft 21 is vertically disposed, and supported by a bearing 47. The crank shaft 21 is contained in the crank case 34. The crank shaft 21 has an upper end connected to a power generation mechanism 51 and a recoil starter 52. As shown in FIG. 1, a flywheel 22 is mounted on a lower end of the crank shaft 21. Also, the lower end of the crank shaft 21 is coupled to a drive shaft 23. The drive shaft 23 passes inside the lower engine cover 13 and the extension cover 14, and is coupled to a power transmission mechanism 24 in the gear case 15.

The power transmission mechanism 24 transmits power of the drive shaft 23 to a horizontal driven shaft 25. The driven shaft 25 protrudes rearward from the gear case 15, and has a rear end to which a propeller 26 is secured. In the outboard motor 10, a pair of dog clutches (not shown) are switched, to switch forward rotation and backward rotation of the propeller 26, thereby obtaining propulsion for forward or backward movement.

As shown in FIG. 2, the engine 11 comprises a vertically oriented cam shaft 53. The cam shaft 53 is supported by a bearing 54 of the cylinder head 32. The cam shaft 53 has a lower end connected to an oil pump 55, and the oil pump 55 is operated with a rotational force of the cam shaft 53. Also, the engine 11 comprises an intake valve 41, an exhaust valve 42, and an ignition plug 43.

Inside the crank case 34, a crank chamber 44 is formed. Under the crank chamber 44, an oil pan 45 is disposed, and in such a structure, oil (engine lubricant) in the crank chamber 44 flows down into the oil pan 45. The engine 11 has a lower part in which a mount case 46 supporting the engine 11 is disposed.

In the vicinity of the cylinder block 33, a main gallery 56 of an oil passage is disposed. An oil filter 57 is provided in a middle of the main gallery 56.

As shown with dashed arrows in FIG. 1, oil in the oil pan 45 is pumped up from a strainer 58 via an oil path 61 with an oil pump 55. The oil pumped up passes from the oil pump 55 through an oil path 62, and is filtered through the oil filter 57. The filtered oil branches and flows upward and downward via the main gallery 56.

The oil in the main gallery 56 is supplied to the bearing 47 of the crank shaft 21 and the like. The oil branching from the main gallery 56 to an oil branch path 63 is supplied via a spool valve 64 and an oil path 65 to the bearing 54 of the cam shaft 53 and the like.

Next, a lubrication mechanism will be described.

FIG. 3 is a perspective view of an oil filter installation member 81 in which the oil filter 57 is installed. FIG. 3 shows the oil filter 57 with an alternate long and short dash line.

As shown in FIG. 3, the oil filter 57 is vertically mounted in an upper part of the oil filter installation member 81. The oil filter installation member 81 is mounted on a side surface of the crank case 34, and has a lower part comprising an inlet oil path 82 and an outlet oil path 83. In the upper part of the oil filter installation member 81, an oil flange 84 is provided to temporarily store lubricant. The oil flange 84 has a flange shape with respect to the oil filter 57. This flange shape is a shape surrounding the oil filter 57.

Also, a filter plate 95 is fitted into the oil flange 84 (FIGS. 4 and 5). The filter plate 95 is a member formed in a tank-like shape covering an entire upper surface of the oil flange 84. The filter plate 95 has a bottom provided with through holes communicating with the inlet oil path 82, the outlet oil path 83, and an after-mentioned relief oil path 90, respectively. The oil filter 57 is mounted on the bottom of the filter plate 95.

The inlet oil path 82 has one end that opens in the oil flange 84, and the inlet oil path 82 has the other end communicating with the oil path 62 (FIG. 1). Also, the outlet oil path 83 has one end that opens in the oil flange 84, and the other end communicating with the main gallery 56 (FIG. 1).

The oil filter installation member 81 comprises a filtered lubricant route to return, to the engine 11, the lubricant filtered through the oil filter 57. This route is a route to circulate the oil pumped up with the oil pump 55 (see FIG. 1) from the inlet oil path 82 to the oil filter 57 as shown with an arrow X, to filter the oil through the oil filter 57, and to return the oil from the outlet oil path 83 to the main gallery 56 (see FIG. 1) as shown with an arrow Y, during an operation of the engine 11.

FIG. 4 is a cross-sectional view showing the oil filter installation member 81 in a state where the oil filter 57 is mounted. FIG. 5 is a cross-sectional view showing the oil filter installation member 81 in a state where the oil filter 57 is removed.

The oil filter installation member 81 comprises the relief oil path 90 that can communicate with the outlet oil path 83. The relief oil path 90 has one end communicating with an oil relief valve 85, and the other end communicating with the oil pan 45 (see FIG. 2) on a lower side of the crank case 34. In the relief oil path 90, the oil relief valve 85 is provided.

The oil filter installation member 81 comprises a lubricant detour route that follows a route other than the filtered lubricant route, to return the lubricant to the engine 11. The lubricant detour route functions, when the engine 11 is stopped, and the oil filter 57 is removed as shown in FIG. 5. This route is a route to return residual lubricant in the oil filter installation member 81 through the relief oil path 90 to the engine 11 as shown with an arrow Z. The lubricant detour route forms a lubricant detour structure, and the detour structure comprises the oil relief valve 85.

FIG. 6 is an exploded perspective view of the oil relief valve 85.

As shown in FIG. 6, the oil relief valve 85 comprises a cylindrical valve guide 86, a spring seat 87, a spring 88, and a piston part 89. The piston part 89 comprises a guide pin 91, and is stored in an upper part of the valve guide 86. The valve guide 86 has an outer circumference formed with a spiral guide hole 92, and the guide pin 91 fits into the guide hole 92. As shown in FIGS. 4 and 5, when the piston part 89 moves in an up-down direction, the guide pin 91 moves through the guide hole 92, and the valve guide 86 rotates within a range of 90°.

The valve guide 86 has a lower end in which a communication hole 93 opens, and the communication hole 93 is disposed in the relief oil path 90 as shown in FIGS. 4 and 5.

In the state of FIG. 4, the oil filter 57 is mounted on the filter plate 95, and the filter plate 95 moves the piston part 89 downward against an urging force of the spring 88. At this time, the communication hole 93 in a tip of the valve guide 86 is orthogonal to the relief oil path 90, and the communication hole 93 is blocked.

When the oil filter 57 is removed, as shown in FIG. 5, the piston part 89 moves upward due to the urging force of the spring 88. With the movement of the piston part 89, the guide pin 91 moves through the guide hole 92, and the valve guide 86 rotates by 90°. The communication hole 93 of the valve guide 86 is parallel to the relief oil path 90, and the communication hole 93 is opened.

The oil filter 57 needs to be periodically replaced. During the operation of the engine 11, as shown with bold dashed arrows in FIG. 1, the oil in the oil pan 45 is pumped up with the oil pump 55, is filtered through the oil filter 57, and flows upward and downward via the vertically oriented main gallery 56. When the engine 11 is stopped, the oil pump 55 is also stopped, but oil remains in the main gallery 56. During the replacement of the oil filter 57, the oil remaining in the main gallery 56 flows out.

In the present embodiment, the oil filter installation member 81 includes the oil flange 84 that stores lubricant, and hence the oil flowing out during the replacement of the oil filter 57 is temporarily collected in the oil flange 84.

When the oil filter 57 is removed, as shown in FIG. 5, the urging force of the spring 88 moves the piston part 89 upward, and the valve guide 86 rotates to open the communication hole 93. The oil temporarily collected in the oil flange 84 flows through the relief oil path 90, to flow down into the oil pan 45 in the crank case 34. Therefore, the oil can be inhibited from scattering out from the oil flange 84.

Next, a new oil filter 57 is vertically mounted in the upper part of the oil filter installation member 81. As shown in FIG. 4, the piston part 89 is pushed by the oil filter 57 to move downward, the valve guide 86 rotates by 90° in reverse, and the communication hole 93 is blocked. The communication hole 93 to the crank case 34 is blocked, and the engine 11 is in an operable state.

The engine according to the present invention is applied to the vertical engine 11 in the embodiment, but may be applied also to a so-called transverse engine.

Any engine including the oil filter 57 mounted at a middle position of the oil passage can be applied, for example, to an engine for a riding lawn mower, tractor or the like.

The oil relief valve includes a configuration that is not limited to the configuration shown in FIG. 6. There are not any special restrictions on the oil relief valve, as long as the valve allows the relief oil path 90 to open in such a manner that the residual lubricant can reflow to the engine 11, when the oil filter 57 is removed.

REFERENCE SIGNS LIST

-   10 outboard motor -   11 engine -   12 upper engine cover -   13 lower engine cover -   21 crank shaft -   32 cylinder head -   33 cylinder block -   34 crank case -   35 combustion chamber -   36 cylinder barrel -   37 piston -   38 connecting rod -   45 oil pan -   55 oil pump -   57 oil filter -   61, 62 and 63 oil path -   63 oil branch path -   81 oil filter installation member -   84 oil flange -   85 oil relief valve -   86 valve guide -   88 spring -   89 piston part -   90 relief oil path -   91 guide pin -   92 guide hole -   93 communication hole 

What is claimed is:
 1. A lubrication mechanism comprising: a vertically disposed crank shaft, a laterally movable piston, a connecting rod connecting the crank shaft and the piston, a cylinder barrel housing the crank shaft and the piston, a crank case containing the crank shaft together with the cylinder barrel, a cylinder head forming a combustion chamber, the combustion chamber connecting to a piston movable part end face of the cylinder barrel, an oil filter, and an oil filter installation member in which the oil filter is vertically installed, wherein the oil filter installation member includes a lubricant detour structure.
 2. The lubrication mechanism according to claim 1, wherein the lubricant detour structure comprises a lubricant detour route formed in the oil filter installation member, and an oil relief valve installed in the lubricant detour route.
 3. The lubrication mechanism according to claim 2, wherein the lubricant detour route follows a route other than a filtered lubricant route of the oil filter to return lubricant to an engine.
 4. The lubrication mechanism according to claim 2, wherein the oil relief valve allows residual lubricant to reflow to the engine, when the oil filter is removed.
 5. The lubrication mechanism according to claim 2, wherein the oil relief valve comprises a cylindrical valve guide, a spring, and a piston part, the valve guide has an outer circumference formed with a spiral guide hole, the piston part includes a guide pin that fits into the guide hole, with movement of the piston part in an up-down direction, the guide pin moves through the guide hole, the valve guide rotates within a range of 90°, the valve guide has a lower end in which a communication hole opens, and the communication hole is disposed in a relief oil path.
 6. The lubrication mechanism according to claim 1, wherein the oil filter installation member has a flange shape with respect to the oil filter.
 7. The lubrication mechanism according to claim 6, wherein the flange shape is a shape surrounding the oil filter.
 8. An outboard motor comprising the lubrication mechanism according to claim
 1. 9. A ship comprising the outboard motor according to claim
 8. 